Massive stars mainly form in close binaries, where their mutual interactions can profoundly alter their evolutionary paths. Evolved binaries consisting of a massive OB-type main-sequence star with a stripped helium star or a compact companion represent a crucial stage in the evolution toward double compact objects, whose mergers are (potentially) detectable via gravitational waves. The recent detection of X-ray-quiet OB+black hole binaries and OB+stripped helium star binaries has set the stage for discovering more of these systems in the near future. In this work, based on 3670 detailed binary-evolution models and using empirical distributions of initial binary parameters, we compute the expected population of such evolved massive binaries in coeval stellar populations, including stars in star clusters and in galaxies with starburst activities, for ages up to 100 Myr. Our results are vividly illustrated in an animation that shows the evolution of these binaries in the color–magnitude diagram over time. We find that the number of OB+black hole binaries peaks around 10 Myr, and OB+neutron star binaries are most abundant at approximately 20 Myr. Both black holes and neutron stars can potentially be found in populations with ages up to 90 Myr. Additionally, we analyze the properties of such binaries at specific ages. We find that OB+helium stars and OB+black hole binaries are likely to be identifiable as single-lined spectroscopic binaries. Our research serves as a guide for future observational efforts to discover such binaries in young star clusters and starburst environments.

中文翻译：

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同时代种群中的剥离氦星和紧凑天体双元：基于详细双星演化模型的预测


大质量恒星主要在紧密的双星中形成，它们的相互作用可以深刻地改变它们的演化路径。由大质量 OB 型主序星和剥离的氦星或致密伴星组成的演化双星代表了向双致密天体演化的关键阶段，其合并（可能）可以通过引力波检测到。最近检测到的 X 射线无干扰 OB+黑洞双星和 OB+剥离的氦星双星为在不久的将来发现更多此类系统奠定了基础。在这项工作中，基于 3670 个详细的双星演化模型并使用初始二进制参数的经验分布，我们计算了同代恒星种群中这种演化的大质量双星的预期数量，包括星团中的恒星和具有星暴活动的星系中的恒星，年龄高达 100 Myr。我们的结果在动画中生动地说明了这些双星在颜色-幅度图中随时间的演变。我们发现 OB+黑洞双星的数量在 10 Myr 左右达到峰值，而 OB+中子星双星在大约 20 Myr 时最丰富。黑洞和中子星都可能在年龄高达 90 Myr 的人群中找到。此外，我们还分析了此类二进制文件在特定年龄的特性。我们发现 OB+氦星和 OB+黑洞双星很可能被识别为单线光谱双星。我们的研究为未来的观测工作提供了指南，以在年轻的星团和星暴环境中发现此类双星。